xref: /openbmc/linux/drivers/mtd/nand/raw/fsmc_nand.c (revision b830f94f)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * ST Microelectronics
4  * Flexible Static Memory Controller (FSMC)
5  * Driver for NAND portions
6  *
7  * Copyright © 2010 ST Microelectronics
8  * Vipin Kumar <vipin.kumar@st.com>
9  * Ashish Priyadarshi
10  *
11  * Based on drivers/mtd/nand/nomadik_nand.c (removed in v3.8)
12  *  Copyright © 2007 STMicroelectronics Pvt. Ltd.
13  *  Copyright © 2009 Alessandro Rubini
14  */
15 
16 #include <linux/clk.h>
17 #include <linux/completion.h>
18 #include <linux/dmaengine.h>
19 #include <linux/dma-direction.h>
20 #include <linux/dma-mapping.h>
21 #include <linux/err.h>
22 #include <linux/init.h>
23 #include <linux/module.h>
24 #include <linux/resource.h>
25 #include <linux/sched.h>
26 #include <linux/types.h>
27 #include <linux/mtd/mtd.h>
28 #include <linux/mtd/rawnand.h>
29 #include <linux/mtd/nand_ecc.h>
30 #include <linux/platform_device.h>
31 #include <linux/of.h>
32 #include <linux/mtd/partitions.h>
33 #include <linux/io.h>
34 #include <linux/slab.h>
35 #include <linux/amba/bus.h>
36 #include <mtd/mtd-abi.h>
37 
38 /* fsmc controller registers for NOR flash */
39 #define CTRL			0x0
40 	/* ctrl register definitions */
41 	#define BANK_ENABLE		BIT(0)
42 	#define MUXED			BIT(1)
43 	#define NOR_DEV			(2 << 2)
44 	#define WIDTH_16		BIT(4)
45 	#define RSTPWRDWN		BIT(6)
46 	#define WPROT			BIT(7)
47 	#define WRT_ENABLE		BIT(12)
48 	#define WAIT_ENB		BIT(13)
49 
50 #define CTRL_TIM		0x4
51 	/* ctrl_tim register definitions */
52 
53 #define FSMC_NOR_BANK_SZ	0x8
54 #define FSMC_NOR_REG_SIZE	0x40
55 
56 #define FSMC_NOR_REG(base, bank, reg)	((base) +			\
57 					 (FSMC_NOR_BANK_SZ * (bank)) +	\
58 					 (reg))
59 
60 /* fsmc controller registers for NAND flash */
61 #define FSMC_PC			0x00
62 	/* pc register definitions */
63 	#define FSMC_RESET		BIT(0)
64 	#define FSMC_WAITON		BIT(1)
65 	#define FSMC_ENABLE		BIT(2)
66 	#define FSMC_DEVTYPE_NAND	BIT(3)
67 	#define FSMC_DEVWID_16		BIT(4)
68 	#define FSMC_ECCEN		BIT(6)
69 	#define FSMC_ECCPLEN_256	BIT(7)
70 	#define FSMC_TCLR_SHIFT		(9)
71 	#define FSMC_TCLR_MASK		(0xF)
72 	#define FSMC_TAR_SHIFT		(13)
73 	#define FSMC_TAR_MASK		(0xF)
74 #define STS			0x04
75 	/* sts register definitions */
76 	#define FSMC_CODE_RDY		BIT(15)
77 #define COMM			0x08
78 	/* comm register definitions */
79 	#define FSMC_TSET_SHIFT		0
80 	#define FSMC_TSET_MASK		0xFF
81 	#define FSMC_TWAIT_SHIFT	8
82 	#define FSMC_TWAIT_MASK		0xFF
83 	#define FSMC_THOLD_SHIFT	16
84 	#define FSMC_THOLD_MASK		0xFF
85 	#define FSMC_THIZ_SHIFT		24
86 	#define FSMC_THIZ_MASK		0xFF
87 #define ATTRIB			0x0C
88 #define IOATA			0x10
89 #define ECC1			0x14
90 #define ECC2			0x18
91 #define ECC3			0x1C
92 #define FSMC_NAND_BANK_SZ	0x20
93 
94 #define FSMC_BUSY_WAIT_TIMEOUT	(1 * HZ)
95 
96 struct fsmc_nand_timings {
97 	u8 tclr;
98 	u8 tar;
99 	u8 thiz;
100 	u8 thold;
101 	u8 twait;
102 	u8 tset;
103 };
104 
105 enum access_mode {
106 	USE_DMA_ACCESS = 1,
107 	USE_WORD_ACCESS,
108 };
109 
110 /**
111  * struct fsmc_nand_data - structure for FSMC NAND device state
112  *
113  * @base:		Inherit from the nand_controller struct
114  * @pid:		Part ID on the AMBA PrimeCell format
115  * @nand:		Chip related info for a NAND flash.
116  *
117  * @bank:		Bank number for probed device.
118  * @dev:		Parent device
119  * @mode:		Access mode
120  * @clk:		Clock structure for FSMC.
121  *
122  * @read_dma_chan:	DMA channel for read access
123  * @write_dma_chan:	DMA channel for write access to NAND
124  * @dma_access_complete: Completion structure
125  *
126  * @dev_timings:	NAND timings
127  *
128  * @data_pa:		NAND Physical port for Data.
129  * @data_va:		NAND port for Data.
130  * @cmd_va:		NAND port for Command.
131  * @addr_va:		NAND port for Address.
132  * @regs_va:		Registers base address for a given bank.
133  */
134 struct fsmc_nand_data {
135 	struct nand_controller	base;
136 	u32			pid;
137 	struct nand_chip	nand;
138 
139 	unsigned int		bank;
140 	struct device		*dev;
141 	enum access_mode	mode;
142 	struct clk		*clk;
143 
144 	/* DMA related objects */
145 	struct dma_chan		*read_dma_chan;
146 	struct dma_chan		*write_dma_chan;
147 	struct completion	dma_access_complete;
148 
149 	struct fsmc_nand_timings *dev_timings;
150 
151 	dma_addr_t		data_pa;
152 	void __iomem		*data_va;
153 	void __iomem		*cmd_va;
154 	void __iomem		*addr_va;
155 	void __iomem		*regs_va;
156 };
157 
158 static int fsmc_ecc1_ooblayout_ecc(struct mtd_info *mtd, int section,
159 				   struct mtd_oob_region *oobregion)
160 {
161 	struct nand_chip *chip = mtd_to_nand(mtd);
162 
163 	if (section >= chip->ecc.steps)
164 		return -ERANGE;
165 
166 	oobregion->offset = (section * 16) + 2;
167 	oobregion->length = 3;
168 
169 	return 0;
170 }
171 
172 static int fsmc_ecc1_ooblayout_free(struct mtd_info *mtd, int section,
173 				    struct mtd_oob_region *oobregion)
174 {
175 	struct nand_chip *chip = mtd_to_nand(mtd);
176 
177 	if (section >= chip->ecc.steps)
178 		return -ERANGE;
179 
180 	oobregion->offset = (section * 16) + 8;
181 
182 	if (section < chip->ecc.steps - 1)
183 		oobregion->length = 8;
184 	else
185 		oobregion->length = mtd->oobsize - oobregion->offset;
186 
187 	return 0;
188 }
189 
190 static const struct mtd_ooblayout_ops fsmc_ecc1_ooblayout_ops = {
191 	.ecc = fsmc_ecc1_ooblayout_ecc,
192 	.free = fsmc_ecc1_ooblayout_free,
193 };
194 
195 /*
196  * ECC placement definitions in oobfree type format.
197  * There are 13 bytes of ecc for every 512 byte block and it has to be read
198  * consecutively and immediately after the 512 byte data block for hardware to
199  * generate the error bit offsets in 512 byte data.
200  */
201 static int fsmc_ecc4_ooblayout_ecc(struct mtd_info *mtd, int section,
202 				   struct mtd_oob_region *oobregion)
203 {
204 	struct nand_chip *chip = mtd_to_nand(mtd);
205 
206 	if (section >= chip->ecc.steps)
207 		return -ERANGE;
208 
209 	oobregion->length = chip->ecc.bytes;
210 
211 	if (!section && mtd->writesize <= 512)
212 		oobregion->offset = 0;
213 	else
214 		oobregion->offset = (section * 16) + 2;
215 
216 	return 0;
217 }
218 
219 static int fsmc_ecc4_ooblayout_free(struct mtd_info *mtd, int section,
220 				    struct mtd_oob_region *oobregion)
221 {
222 	struct nand_chip *chip = mtd_to_nand(mtd);
223 
224 	if (section >= chip->ecc.steps)
225 		return -ERANGE;
226 
227 	oobregion->offset = (section * 16) + 15;
228 
229 	if (section < chip->ecc.steps - 1)
230 		oobregion->length = 3;
231 	else
232 		oobregion->length = mtd->oobsize - oobregion->offset;
233 
234 	return 0;
235 }
236 
237 static const struct mtd_ooblayout_ops fsmc_ecc4_ooblayout_ops = {
238 	.ecc = fsmc_ecc4_ooblayout_ecc,
239 	.free = fsmc_ecc4_ooblayout_free,
240 };
241 
242 static inline struct fsmc_nand_data *nand_to_fsmc(struct nand_chip *chip)
243 {
244 	return container_of(chip, struct fsmc_nand_data, nand);
245 }
246 
247 /*
248  * fsmc_nand_setup - FSMC (Flexible Static Memory Controller) init routine
249  *
250  * This routine initializes timing parameters related to NAND memory access in
251  * FSMC registers
252  */
253 static void fsmc_nand_setup(struct fsmc_nand_data *host,
254 			    struct fsmc_nand_timings *tims)
255 {
256 	u32 value = FSMC_DEVTYPE_NAND | FSMC_ENABLE | FSMC_WAITON;
257 	u32 tclr, tar, thiz, thold, twait, tset;
258 
259 	tclr = (tims->tclr & FSMC_TCLR_MASK) << FSMC_TCLR_SHIFT;
260 	tar = (tims->tar & FSMC_TAR_MASK) << FSMC_TAR_SHIFT;
261 	thiz = (tims->thiz & FSMC_THIZ_MASK) << FSMC_THIZ_SHIFT;
262 	thold = (tims->thold & FSMC_THOLD_MASK) << FSMC_THOLD_SHIFT;
263 	twait = (tims->twait & FSMC_TWAIT_MASK) << FSMC_TWAIT_SHIFT;
264 	tset = (tims->tset & FSMC_TSET_MASK) << FSMC_TSET_SHIFT;
265 
266 	if (host->nand.options & NAND_BUSWIDTH_16)
267 		value |= FSMC_DEVWID_16;
268 
269 	writel_relaxed(value | tclr | tar, host->regs_va + FSMC_PC);
270 	writel_relaxed(thiz | thold | twait | tset, host->regs_va + COMM);
271 	writel_relaxed(thiz | thold | twait | tset, host->regs_va + ATTRIB);
272 }
273 
274 static int fsmc_calc_timings(struct fsmc_nand_data *host,
275 			     const struct nand_sdr_timings *sdrt,
276 			     struct fsmc_nand_timings *tims)
277 {
278 	unsigned long hclk = clk_get_rate(host->clk);
279 	unsigned long hclkn = NSEC_PER_SEC / hclk;
280 	u32 thiz, thold, twait, tset;
281 
282 	if (sdrt->tRC_min < 30000)
283 		return -EOPNOTSUPP;
284 
285 	tims->tar = DIV_ROUND_UP(sdrt->tAR_min / 1000, hclkn) - 1;
286 	if (tims->tar > FSMC_TAR_MASK)
287 		tims->tar = FSMC_TAR_MASK;
288 	tims->tclr = DIV_ROUND_UP(sdrt->tCLR_min / 1000, hclkn) - 1;
289 	if (tims->tclr > FSMC_TCLR_MASK)
290 		tims->tclr = FSMC_TCLR_MASK;
291 
292 	thiz = sdrt->tCS_min - sdrt->tWP_min;
293 	tims->thiz = DIV_ROUND_UP(thiz / 1000, hclkn);
294 
295 	thold = sdrt->tDH_min;
296 	if (thold < sdrt->tCH_min)
297 		thold = sdrt->tCH_min;
298 	if (thold < sdrt->tCLH_min)
299 		thold = sdrt->tCLH_min;
300 	if (thold < sdrt->tWH_min)
301 		thold = sdrt->tWH_min;
302 	if (thold < sdrt->tALH_min)
303 		thold = sdrt->tALH_min;
304 	if (thold < sdrt->tREH_min)
305 		thold = sdrt->tREH_min;
306 	tims->thold = DIV_ROUND_UP(thold / 1000, hclkn);
307 	if (tims->thold == 0)
308 		tims->thold = 1;
309 	else if (tims->thold > FSMC_THOLD_MASK)
310 		tims->thold = FSMC_THOLD_MASK;
311 
312 	twait = max(sdrt->tRP_min, sdrt->tWP_min);
313 	tims->twait = DIV_ROUND_UP(twait / 1000, hclkn) - 1;
314 	if (tims->twait == 0)
315 		tims->twait = 1;
316 	else if (tims->twait > FSMC_TWAIT_MASK)
317 		tims->twait = FSMC_TWAIT_MASK;
318 
319 	tset = max(sdrt->tCS_min - sdrt->tWP_min,
320 		   sdrt->tCEA_max - sdrt->tREA_max);
321 	tims->tset = DIV_ROUND_UP(tset / 1000, hclkn) - 1;
322 	if (tims->tset == 0)
323 		tims->tset = 1;
324 	else if (tims->tset > FSMC_TSET_MASK)
325 		tims->tset = FSMC_TSET_MASK;
326 
327 	return 0;
328 }
329 
330 static int fsmc_setup_data_interface(struct nand_chip *nand, int csline,
331 				     const struct nand_data_interface *conf)
332 {
333 	struct fsmc_nand_data *host = nand_to_fsmc(nand);
334 	struct fsmc_nand_timings tims;
335 	const struct nand_sdr_timings *sdrt;
336 	int ret;
337 
338 	sdrt = nand_get_sdr_timings(conf);
339 	if (IS_ERR(sdrt))
340 		return PTR_ERR(sdrt);
341 
342 	ret = fsmc_calc_timings(host, sdrt, &tims);
343 	if (ret)
344 		return ret;
345 
346 	if (csline == NAND_DATA_IFACE_CHECK_ONLY)
347 		return 0;
348 
349 	fsmc_nand_setup(host, &tims);
350 
351 	return 0;
352 }
353 
354 /*
355  * fsmc_enable_hwecc - Enables Hardware ECC through FSMC registers
356  */
357 static void fsmc_enable_hwecc(struct nand_chip *chip, int mode)
358 {
359 	struct fsmc_nand_data *host = nand_to_fsmc(chip);
360 
361 	writel_relaxed(readl(host->regs_va + FSMC_PC) & ~FSMC_ECCPLEN_256,
362 		       host->regs_va + FSMC_PC);
363 	writel_relaxed(readl(host->regs_va + FSMC_PC) & ~FSMC_ECCEN,
364 		       host->regs_va + FSMC_PC);
365 	writel_relaxed(readl(host->regs_va + FSMC_PC) | FSMC_ECCEN,
366 		       host->regs_va + FSMC_PC);
367 }
368 
369 /*
370  * fsmc_read_hwecc_ecc4 - Hardware ECC calculator for ecc4 option supported by
371  * FSMC. ECC is 13 bytes for 512 bytes of data (supports error correction up to
372  * max of 8-bits)
373  */
374 static int fsmc_read_hwecc_ecc4(struct nand_chip *chip, const u8 *data,
375 				u8 *ecc)
376 {
377 	struct fsmc_nand_data *host = nand_to_fsmc(chip);
378 	u32 ecc_tmp;
379 	unsigned long deadline = jiffies + FSMC_BUSY_WAIT_TIMEOUT;
380 
381 	do {
382 		if (readl_relaxed(host->regs_va + STS) & FSMC_CODE_RDY)
383 			break;
384 
385 		cond_resched();
386 	} while (!time_after_eq(jiffies, deadline));
387 
388 	if (time_after_eq(jiffies, deadline)) {
389 		dev_err(host->dev, "calculate ecc timed out\n");
390 		return -ETIMEDOUT;
391 	}
392 
393 	ecc_tmp = readl_relaxed(host->regs_va + ECC1);
394 	ecc[0] = ecc_tmp;
395 	ecc[1] = ecc_tmp >> 8;
396 	ecc[2] = ecc_tmp >> 16;
397 	ecc[3] = ecc_tmp >> 24;
398 
399 	ecc_tmp = readl_relaxed(host->regs_va + ECC2);
400 	ecc[4] = ecc_tmp;
401 	ecc[5] = ecc_tmp >> 8;
402 	ecc[6] = ecc_tmp >> 16;
403 	ecc[7] = ecc_tmp >> 24;
404 
405 	ecc_tmp = readl_relaxed(host->regs_va + ECC3);
406 	ecc[8] = ecc_tmp;
407 	ecc[9] = ecc_tmp >> 8;
408 	ecc[10] = ecc_tmp >> 16;
409 	ecc[11] = ecc_tmp >> 24;
410 
411 	ecc_tmp = readl_relaxed(host->regs_va + STS);
412 	ecc[12] = ecc_tmp >> 16;
413 
414 	return 0;
415 }
416 
417 /*
418  * fsmc_read_hwecc_ecc1 - Hardware ECC calculator for ecc1 option supported by
419  * FSMC. ECC is 3 bytes for 512 bytes of data (supports error correction up to
420  * max of 1-bit)
421  */
422 static int fsmc_read_hwecc_ecc1(struct nand_chip *chip, const u8 *data,
423 				u8 *ecc)
424 {
425 	struct fsmc_nand_data *host = nand_to_fsmc(chip);
426 	u32 ecc_tmp;
427 
428 	ecc_tmp = readl_relaxed(host->regs_va + ECC1);
429 	ecc[0] = ecc_tmp;
430 	ecc[1] = ecc_tmp >> 8;
431 	ecc[2] = ecc_tmp >> 16;
432 
433 	return 0;
434 }
435 
436 /* Count the number of 0's in buff upto a max of max_bits */
437 static int count_written_bits(u8 *buff, int size, int max_bits)
438 {
439 	int k, written_bits = 0;
440 
441 	for (k = 0; k < size; k++) {
442 		written_bits += hweight8(~buff[k]);
443 		if (written_bits > max_bits)
444 			break;
445 	}
446 
447 	return written_bits;
448 }
449 
450 static void dma_complete(void *param)
451 {
452 	struct fsmc_nand_data *host = param;
453 
454 	complete(&host->dma_access_complete);
455 }
456 
457 static int dma_xfer(struct fsmc_nand_data *host, void *buffer, int len,
458 		    enum dma_data_direction direction)
459 {
460 	struct dma_chan *chan;
461 	struct dma_device *dma_dev;
462 	struct dma_async_tx_descriptor *tx;
463 	dma_addr_t dma_dst, dma_src, dma_addr;
464 	dma_cookie_t cookie;
465 	unsigned long flags = DMA_CTRL_ACK | DMA_PREP_INTERRUPT;
466 	int ret;
467 	unsigned long time_left;
468 
469 	if (direction == DMA_TO_DEVICE)
470 		chan = host->write_dma_chan;
471 	else if (direction == DMA_FROM_DEVICE)
472 		chan = host->read_dma_chan;
473 	else
474 		return -EINVAL;
475 
476 	dma_dev = chan->device;
477 	dma_addr = dma_map_single(dma_dev->dev, buffer, len, direction);
478 
479 	if (direction == DMA_TO_DEVICE) {
480 		dma_src = dma_addr;
481 		dma_dst = host->data_pa;
482 	} else {
483 		dma_src = host->data_pa;
484 		dma_dst = dma_addr;
485 	}
486 
487 	tx = dma_dev->device_prep_dma_memcpy(chan, dma_dst, dma_src,
488 			len, flags);
489 	if (!tx) {
490 		dev_err(host->dev, "device_prep_dma_memcpy error\n");
491 		ret = -EIO;
492 		goto unmap_dma;
493 	}
494 
495 	tx->callback = dma_complete;
496 	tx->callback_param = host;
497 	cookie = tx->tx_submit(tx);
498 
499 	ret = dma_submit_error(cookie);
500 	if (ret) {
501 		dev_err(host->dev, "dma_submit_error %d\n", cookie);
502 		goto unmap_dma;
503 	}
504 
505 	dma_async_issue_pending(chan);
506 
507 	time_left =
508 	wait_for_completion_timeout(&host->dma_access_complete,
509 				    msecs_to_jiffies(3000));
510 	if (time_left == 0) {
511 		dmaengine_terminate_all(chan);
512 		dev_err(host->dev, "wait_for_completion_timeout\n");
513 		ret = -ETIMEDOUT;
514 		goto unmap_dma;
515 	}
516 
517 	ret = 0;
518 
519 unmap_dma:
520 	dma_unmap_single(dma_dev->dev, dma_addr, len, direction);
521 
522 	return ret;
523 }
524 
525 /*
526  * fsmc_write_buf - write buffer to chip
527  * @host:	FSMC NAND controller
528  * @buf:	data buffer
529  * @len:	number of bytes to write
530  */
531 static void fsmc_write_buf(struct fsmc_nand_data *host, const u8 *buf,
532 			   int len)
533 {
534 	int i;
535 
536 	if (IS_ALIGNED((uintptr_t)buf, sizeof(u32)) &&
537 	    IS_ALIGNED(len, sizeof(u32))) {
538 		u32 *p = (u32 *)buf;
539 
540 		len = len >> 2;
541 		for (i = 0; i < len; i++)
542 			writel_relaxed(p[i], host->data_va);
543 	} else {
544 		for (i = 0; i < len; i++)
545 			writeb_relaxed(buf[i], host->data_va);
546 	}
547 }
548 
549 /*
550  * fsmc_read_buf - read chip data into buffer
551  * @host:	FSMC NAND controller
552  * @buf:	buffer to store date
553  * @len:	number of bytes to read
554  */
555 static void fsmc_read_buf(struct fsmc_nand_data *host, u8 *buf, int len)
556 {
557 	int i;
558 
559 	if (IS_ALIGNED((uintptr_t)buf, sizeof(u32)) &&
560 	    IS_ALIGNED(len, sizeof(u32))) {
561 		u32 *p = (u32 *)buf;
562 
563 		len = len >> 2;
564 		for (i = 0; i < len; i++)
565 			p[i] = readl_relaxed(host->data_va);
566 	} else {
567 		for (i = 0; i < len; i++)
568 			buf[i] = readb_relaxed(host->data_va);
569 	}
570 }
571 
572 /*
573  * fsmc_read_buf_dma - read chip data into buffer
574  * @host:	FSMC NAND controller
575  * @buf:	buffer to store date
576  * @len:	number of bytes to read
577  */
578 static void fsmc_read_buf_dma(struct fsmc_nand_data *host, u8 *buf,
579 			      int len)
580 {
581 	dma_xfer(host, buf, len, DMA_FROM_DEVICE);
582 }
583 
584 /*
585  * fsmc_write_buf_dma - write buffer to chip
586  * @host:	FSMC NAND controller
587  * @buf:	data buffer
588  * @len:	number of bytes to write
589  */
590 static void fsmc_write_buf_dma(struct fsmc_nand_data *host, const u8 *buf,
591 			       int len)
592 {
593 	dma_xfer(host, (void *)buf, len, DMA_TO_DEVICE);
594 }
595 
596 /*
597  * fsmc_exec_op - hook called by the core to execute NAND operations
598  *
599  * This controller is simple enough and thus does not need to use the parser
600  * provided by the core, instead, handle every situation here.
601  */
602 static int fsmc_exec_op(struct nand_chip *chip, const struct nand_operation *op,
603 			bool check_only)
604 {
605 	struct fsmc_nand_data *host = nand_to_fsmc(chip);
606 	const struct nand_op_instr *instr = NULL;
607 	int ret = 0;
608 	unsigned int op_id;
609 	int i;
610 
611 	pr_debug("Executing operation [%d instructions]:\n", op->ninstrs);
612 
613 	for (op_id = 0; op_id < op->ninstrs; op_id++) {
614 		instr = &op->instrs[op_id];
615 
616 		nand_op_trace("  ", instr);
617 
618 		switch (instr->type) {
619 		case NAND_OP_CMD_INSTR:
620 			writeb_relaxed(instr->ctx.cmd.opcode, host->cmd_va);
621 			break;
622 
623 		case NAND_OP_ADDR_INSTR:
624 			for (i = 0; i < instr->ctx.addr.naddrs; i++)
625 				writeb_relaxed(instr->ctx.addr.addrs[i],
626 					       host->addr_va);
627 			break;
628 
629 		case NAND_OP_DATA_IN_INSTR:
630 			if (host->mode == USE_DMA_ACCESS)
631 				fsmc_read_buf_dma(host, instr->ctx.data.buf.in,
632 						  instr->ctx.data.len);
633 			else
634 				fsmc_read_buf(host, instr->ctx.data.buf.in,
635 					      instr->ctx.data.len);
636 			break;
637 
638 		case NAND_OP_DATA_OUT_INSTR:
639 			if (host->mode == USE_DMA_ACCESS)
640 				fsmc_write_buf_dma(host,
641 						   instr->ctx.data.buf.out,
642 						   instr->ctx.data.len);
643 			else
644 				fsmc_write_buf(host, instr->ctx.data.buf.out,
645 					       instr->ctx.data.len);
646 			break;
647 
648 		case NAND_OP_WAITRDY_INSTR:
649 			ret = nand_soft_waitrdy(chip,
650 						instr->ctx.waitrdy.timeout_ms);
651 			break;
652 		}
653 	}
654 
655 	return ret;
656 }
657 
658 /*
659  * fsmc_read_page_hwecc
660  * @chip:	nand chip info structure
661  * @buf:	buffer to store read data
662  * @oob_required:	caller expects OOB data read to chip->oob_poi
663  * @page:	page number to read
664  *
665  * This routine is needed for fsmc version 8 as reading from NAND chip has to be
666  * performed in a strict sequence as follows:
667  * data(512 byte) -> ecc(13 byte)
668  * After this read, fsmc hardware generates and reports error data bits(up to a
669  * max of 8 bits)
670  */
671 static int fsmc_read_page_hwecc(struct nand_chip *chip, u8 *buf,
672 				int oob_required, int page)
673 {
674 	struct mtd_info *mtd = nand_to_mtd(chip);
675 	int i, j, s, stat, eccsize = chip->ecc.size;
676 	int eccbytes = chip->ecc.bytes;
677 	int eccsteps = chip->ecc.steps;
678 	u8 *p = buf;
679 	u8 *ecc_calc = chip->ecc.calc_buf;
680 	u8 *ecc_code = chip->ecc.code_buf;
681 	int off, len, ret, group = 0;
682 	/*
683 	 * ecc_oob is intentionally taken as u16. In 16bit devices, we
684 	 * end up reading 14 bytes (7 words) from oob. The local array is
685 	 * to maintain word alignment
686 	 */
687 	u16 ecc_oob[7];
688 	u8 *oob = (u8 *)&ecc_oob[0];
689 	unsigned int max_bitflips = 0;
690 
691 	for (i = 0, s = 0; s < eccsteps; s++, i += eccbytes, p += eccsize) {
692 		nand_read_page_op(chip, page, s * eccsize, NULL, 0);
693 		chip->ecc.hwctl(chip, NAND_ECC_READ);
694 		ret = nand_read_data_op(chip, p, eccsize, false);
695 		if (ret)
696 			return ret;
697 
698 		for (j = 0; j < eccbytes;) {
699 			struct mtd_oob_region oobregion;
700 
701 			ret = mtd_ooblayout_ecc(mtd, group++, &oobregion);
702 			if (ret)
703 				return ret;
704 
705 			off = oobregion.offset;
706 			len = oobregion.length;
707 
708 			/*
709 			 * length is intentionally kept a higher multiple of 2
710 			 * to read at least 13 bytes even in case of 16 bit NAND
711 			 * devices
712 			 */
713 			if (chip->options & NAND_BUSWIDTH_16)
714 				len = roundup(len, 2);
715 
716 			nand_read_oob_op(chip, page, off, oob + j, len);
717 			j += len;
718 		}
719 
720 		memcpy(&ecc_code[i], oob, chip->ecc.bytes);
721 		chip->ecc.calculate(chip, p, &ecc_calc[i]);
722 
723 		stat = chip->ecc.correct(chip, p, &ecc_code[i], &ecc_calc[i]);
724 		if (stat < 0) {
725 			mtd->ecc_stats.failed++;
726 		} else {
727 			mtd->ecc_stats.corrected += stat;
728 			max_bitflips = max_t(unsigned int, max_bitflips, stat);
729 		}
730 	}
731 
732 	return max_bitflips;
733 }
734 
735 /*
736  * fsmc_bch8_correct_data
737  * @mtd:	mtd info structure
738  * @dat:	buffer of read data
739  * @read_ecc:	ecc read from device spare area
740  * @calc_ecc:	ecc calculated from read data
741  *
742  * calc_ecc is a 104 bit information containing maximum of 8 error
743  * offset information of 13 bits each in 512 bytes of read data.
744  */
745 static int fsmc_bch8_correct_data(struct nand_chip *chip, u8 *dat,
746 				  u8 *read_ecc, u8 *calc_ecc)
747 {
748 	struct fsmc_nand_data *host = nand_to_fsmc(chip);
749 	u32 err_idx[8];
750 	u32 num_err, i;
751 	u32 ecc1, ecc2, ecc3, ecc4;
752 
753 	num_err = (readl_relaxed(host->regs_va + STS) >> 10) & 0xF;
754 
755 	/* no bit flipping */
756 	if (likely(num_err == 0))
757 		return 0;
758 
759 	/* too many errors */
760 	if (unlikely(num_err > 8)) {
761 		/*
762 		 * This is a temporary erase check. A newly erased page read
763 		 * would result in an ecc error because the oob data is also
764 		 * erased to FF and the calculated ecc for an FF data is not
765 		 * FF..FF.
766 		 * This is a workaround to skip performing correction in case
767 		 * data is FF..FF
768 		 *
769 		 * Logic:
770 		 * For every page, each bit written as 0 is counted until these
771 		 * number of bits are greater than 8 (the maximum correction
772 		 * capability of FSMC for each 512 + 13 bytes)
773 		 */
774 
775 		int bits_ecc = count_written_bits(read_ecc, chip->ecc.bytes, 8);
776 		int bits_data = count_written_bits(dat, chip->ecc.size, 8);
777 
778 		if ((bits_ecc + bits_data) <= 8) {
779 			if (bits_data)
780 				memset(dat, 0xff, chip->ecc.size);
781 			return bits_data;
782 		}
783 
784 		return -EBADMSG;
785 	}
786 
787 	/*
788 	 * ------------------- calc_ecc[] bit wise -----------|--13 bits--|
789 	 * |---idx[7]--|--.....-----|---idx[2]--||---idx[1]--||---idx[0]--|
790 	 *
791 	 * calc_ecc is a 104 bit information containing maximum of 8 error
792 	 * offset information of 13 bits each. calc_ecc is copied into a
793 	 * u64 array and error offset indexes are populated in err_idx
794 	 * array
795 	 */
796 	ecc1 = readl_relaxed(host->regs_va + ECC1);
797 	ecc2 = readl_relaxed(host->regs_va + ECC2);
798 	ecc3 = readl_relaxed(host->regs_va + ECC3);
799 	ecc4 = readl_relaxed(host->regs_va + STS);
800 
801 	err_idx[0] = (ecc1 >> 0) & 0x1FFF;
802 	err_idx[1] = (ecc1 >> 13) & 0x1FFF;
803 	err_idx[2] = (((ecc2 >> 0) & 0x7F) << 6) | ((ecc1 >> 26) & 0x3F);
804 	err_idx[3] = (ecc2 >> 7) & 0x1FFF;
805 	err_idx[4] = (((ecc3 >> 0) & 0x1) << 12) | ((ecc2 >> 20) & 0xFFF);
806 	err_idx[5] = (ecc3 >> 1) & 0x1FFF;
807 	err_idx[6] = (ecc3 >> 14) & 0x1FFF;
808 	err_idx[7] = (((ecc4 >> 16) & 0xFF) << 5) | ((ecc3 >> 27) & 0x1F);
809 
810 	i = 0;
811 	while (num_err--) {
812 		change_bit(0, (unsigned long *)&err_idx[i]);
813 		change_bit(1, (unsigned long *)&err_idx[i]);
814 
815 		if (err_idx[i] < chip->ecc.size * 8) {
816 			change_bit(err_idx[i], (unsigned long *)dat);
817 			i++;
818 		}
819 	}
820 	return i;
821 }
822 
823 static bool filter(struct dma_chan *chan, void *slave)
824 {
825 	chan->private = slave;
826 	return true;
827 }
828 
829 static int fsmc_nand_probe_config_dt(struct platform_device *pdev,
830 				     struct fsmc_nand_data *host,
831 				     struct nand_chip *nand)
832 {
833 	struct device_node *np = pdev->dev.of_node;
834 	u32 val;
835 	int ret;
836 
837 	nand->options = 0;
838 
839 	if (!of_property_read_u32(np, "bank-width", &val)) {
840 		if (val == 2) {
841 			nand->options |= NAND_BUSWIDTH_16;
842 		} else if (val != 1) {
843 			dev_err(&pdev->dev, "invalid bank-width %u\n", val);
844 			return -EINVAL;
845 		}
846 	}
847 
848 	if (of_get_property(np, "nand-skip-bbtscan", NULL))
849 		nand->options |= NAND_SKIP_BBTSCAN;
850 
851 	host->dev_timings = devm_kzalloc(&pdev->dev,
852 					 sizeof(*host->dev_timings),
853 					 GFP_KERNEL);
854 	if (!host->dev_timings)
855 		return -ENOMEM;
856 
857 	ret = of_property_read_u8_array(np, "timings", (u8 *)host->dev_timings,
858 					sizeof(*host->dev_timings));
859 	if (ret)
860 		host->dev_timings = NULL;
861 
862 	/* Set default NAND bank to 0 */
863 	host->bank = 0;
864 	if (!of_property_read_u32(np, "bank", &val)) {
865 		if (val > 3) {
866 			dev_err(&pdev->dev, "invalid bank %u\n", val);
867 			return -EINVAL;
868 		}
869 		host->bank = val;
870 	}
871 	return 0;
872 }
873 
874 static int fsmc_nand_attach_chip(struct nand_chip *nand)
875 {
876 	struct mtd_info *mtd = nand_to_mtd(nand);
877 	struct fsmc_nand_data *host = nand_to_fsmc(nand);
878 
879 	if (AMBA_REV_BITS(host->pid) >= 8) {
880 		switch (mtd->oobsize) {
881 		case 16:
882 		case 64:
883 		case 128:
884 		case 224:
885 		case 256:
886 			break;
887 		default:
888 			dev_warn(host->dev,
889 				 "No oob scheme defined for oobsize %d\n",
890 				 mtd->oobsize);
891 			return -EINVAL;
892 		}
893 
894 		mtd_set_ooblayout(mtd, &fsmc_ecc4_ooblayout_ops);
895 
896 		return 0;
897 	}
898 
899 	switch (nand->ecc.mode) {
900 	case NAND_ECC_HW:
901 		dev_info(host->dev, "Using 1-bit HW ECC scheme\n");
902 		nand->ecc.calculate = fsmc_read_hwecc_ecc1;
903 		nand->ecc.correct = nand_correct_data;
904 		nand->ecc.bytes = 3;
905 		nand->ecc.strength = 1;
906 		nand->ecc.options |= NAND_ECC_SOFT_HAMMING_SM_ORDER;
907 		break;
908 
909 	case NAND_ECC_SOFT:
910 		if (nand->ecc.algo == NAND_ECC_BCH) {
911 			dev_info(host->dev,
912 				 "Using 4-bit SW BCH ECC scheme\n");
913 			break;
914 		}
915 
916 	case NAND_ECC_ON_DIE:
917 		break;
918 
919 	default:
920 		dev_err(host->dev, "Unsupported ECC mode!\n");
921 		return -ENOTSUPP;
922 	}
923 
924 	/*
925 	 * Don't set layout for BCH4 SW ECC. This will be
926 	 * generated later in nand_bch_init() later.
927 	 */
928 	if (nand->ecc.mode == NAND_ECC_HW) {
929 		switch (mtd->oobsize) {
930 		case 16:
931 		case 64:
932 		case 128:
933 			mtd_set_ooblayout(mtd,
934 					  &fsmc_ecc1_ooblayout_ops);
935 			break;
936 		default:
937 			dev_warn(host->dev,
938 				 "No oob scheme defined for oobsize %d\n",
939 				 mtd->oobsize);
940 			return -EINVAL;
941 		}
942 	}
943 
944 	return 0;
945 }
946 
947 static const struct nand_controller_ops fsmc_nand_controller_ops = {
948 	.attach_chip = fsmc_nand_attach_chip,
949 	.exec_op = fsmc_exec_op,
950 	.setup_data_interface = fsmc_setup_data_interface,
951 };
952 
953 /**
954  * fsmc_nand_disable() - Disables the NAND bank
955  * @host: The instance to disable
956  */
957 static void fsmc_nand_disable(struct fsmc_nand_data *host)
958 {
959 	u32 val;
960 
961 	val = readl(host->regs_va + FSMC_PC);
962 	val &= ~FSMC_ENABLE;
963 	writel(val, host->regs_va + FSMC_PC);
964 }
965 
966 /*
967  * fsmc_nand_probe - Probe function
968  * @pdev:       platform device structure
969  */
970 static int __init fsmc_nand_probe(struct platform_device *pdev)
971 {
972 	struct fsmc_nand_data *host;
973 	struct mtd_info *mtd;
974 	struct nand_chip *nand;
975 	struct resource *res;
976 	void __iomem *base;
977 	dma_cap_mask_t mask;
978 	int ret = 0;
979 	u32 pid;
980 	int i;
981 
982 	/* Allocate memory for the device structure (and zero it) */
983 	host = devm_kzalloc(&pdev->dev, sizeof(*host), GFP_KERNEL);
984 	if (!host)
985 		return -ENOMEM;
986 
987 	nand = &host->nand;
988 
989 	ret = fsmc_nand_probe_config_dt(pdev, host, nand);
990 	if (ret)
991 		return ret;
992 
993 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "nand_data");
994 	host->data_va = devm_ioremap_resource(&pdev->dev, res);
995 	if (IS_ERR(host->data_va))
996 		return PTR_ERR(host->data_va);
997 
998 	host->data_pa = (dma_addr_t)res->start;
999 
1000 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "nand_addr");
1001 	host->addr_va = devm_ioremap_resource(&pdev->dev, res);
1002 	if (IS_ERR(host->addr_va))
1003 		return PTR_ERR(host->addr_va);
1004 
1005 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "nand_cmd");
1006 	host->cmd_va = devm_ioremap_resource(&pdev->dev, res);
1007 	if (IS_ERR(host->cmd_va))
1008 		return PTR_ERR(host->cmd_va);
1009 
1010 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "fsmc_regs");
1011 	base = devm_ioremap_resource(&pdev->dev, res);
1012 	if (IS_ERR(base))
1013 		return PTR_ERR(base);
1014 
1015 	host->regs_va = base + FSMC_NOR_REG_SIZE +
1016 		(host->bank * FSMC_NAND_BANK_SZ);
1017 
1018 	host->clk = devm_clk_get(&pdev->dev, NULL);
1019 	if (IS_ERR(host->clk)) {
1020 		dev_err(&pdev->dev, "failed to fetch block clock\n");
1021 		return PTR_ERR(host->clk);
1022 	}
1023 
1024 	ret = clk_prepare_enable(host->clk);
1025 	if (ret)
1026 		return ret;
1027 
1028 	/*
1029 	 * This device ID is actually a common AMBA ID as used on the
1030 	 * AMBA PrimeCell bus. However it is not a PrimeCell.
1031 	 */
1032 	for (pid = 0, i = 0; i < 4; i++)
1033 		pid |= (readl(base + resource_size(res) - 0x20 + 4 * i) &
1034 			255) << (i * 8);
1035 
1036 	host->pid = pid;
1037 
1038 	dev_info(&pdev->dev,
1039 		 "FSMC device partno %03x, manufacturer %02x, revision %02x, config %02x\n",
1040 		 AMBA_PART_BITS(pid), AMBA_MANF_BITS(pid),
1041 		 AMBA_REV_BITS(pid), AMBA_CONFIG_BITS(pid));
1042 
1043 	host->dev = &pdev->dev;
1044 
1045 	if (host->mode == USE_DMA_ACCESS)
1046 		init_completion(&host->dma_access_complete);
1047 
1048 	/* Link all private pointers */
1049 	mtd = nand_to_mtd(&host->nand);
1050 	nand_set_flash_node(nand, pdev->dev.of_node);
1051 
1052 	mtd->dev.parent = &pdev->dev;
1053 
1054 	/*
1055 	 * Setup default ECC mode. nand_dt_init() called from nand_scan_ident()
1056 	 * can overwrite this value if the DT provides a different value.
1057 	 */
1058 	nand->ecc.mode = NAND_ECC_HW;
1059 	nand->ecc.hwctl = fsmc_enable_hwecc;
1060 	nand->ecc.size = 512;
1061 	nand->badblockbits = 7;
1062 
1063 	if (host->mode == USE_DMA_ACCESS) {
1064 		dma_cap_zero(mask);
1065 		dma_cap_set(DMA_MEMCPY, mask);
1066 		host->read_dma_chan = dma_request_channel(mask, filter, NULL);
1067 		if (!host->read_dma_chan) {
1068 			dev_err(&pdev->dev, "Unable to get read dma channel\n");
1069 			goto disable_clk;
1070 		}
1071 		host->write_dma_chan = dma_request_channel(mask, filter, NULL);
1072 		if (!host->write_dma_chan) {
1073 			dev_err(&pdev->dev, "Unable to get write dma channel\n");
1074 			goto release_dma_read_chan;
1075 		}
1076 	}
1077 
1078 	if (host->dev_timings) {
1079 		fsmc_nand_setup(host, host->dev_timings);
1080 		nand->options |= NAND_KEEP_TIMINGS;
1081 	}
1082 
1083 	if (AMBA_REV_BITS(host->pid) >= 8) {
1084 		nand->ecc.read_page = fsmc_read_page_hwecc;
1085 		nand->ecc.calculate = fsmc_read_hwecc_ecc4;
1086 		nand->ecc.correct = fsmc_bch8_correct_data;
1087 		nand->ecc.bytes = 13;
1088 		nand->ecc.strength = 8;
1089 	}
1090 
1091 	nand_controller_init(&host->base);
1092 	host->base.ops = &fsmc_nand_controller_ops;
1093 	nand->controller = &host->base;
1094 
1095 	/*
1096 	 * Scan to find existence of the device
1097 	 */
1098 	ret = nand_scan(nand, 1);
1099 	if (ret)
1100 		goto release_dma_write_chan;
1101 
1102 	mtd->name = "nand";
1103 	ret = mtd_device_register(mtd, NULL, 0);
1104 	if (ret)
1105 		goto cleanup_nand;
1106 
1107 	platform_set_drvdata(pdev, host);
1108 	dev_info(&pdev->dev, "FSMC NAND driver registration successful\n");
1109 
1110 	return 0;
1111 
1112 cleanup_nand:
1113 	nand_cleanup(nand);
1114 release_dma_write_chan:
1115 	if (host->mode == USE_DMA_ACCESS)
1116 		dma_release_channel(host->write_dma_chan);
1117 release_dma_read_chan:
1118 	if (host->mode == USE_DMA_ACCESS)
1119 		dma_release_channel(host->read_dma_chan);
1120 disable_clk:
1121 	fsmc_nand_disable(host);
1122 	clk_disable_unprepare(host->clk);
1123 
1124 	return ret;
1125 }
1126 
1127 /*
1128  * Clean up routine
1129  */
1130 static int fsmc_nand_remove(struct platform_device *pdev)
1131 {
1132 	struct fsmc_nand_data *host = platform_get_drvdata(pdev);
1133 
1134 	if (host) {
1135 		nand_release(&host->nand);
1136 		fsmc_nand_disable(host);
1137 
1138 		if (host->mode == USE_DMA_ACCESS) {
1139 			dma_release_channel(host->write_dma_chan);
1140 			dma_release_channel(host->read_dma_chan);
1141 		}
1142 		clk_disable_unprepare(host->clk);
1143 	}
1144 
1145 	return 0;
1146 }
1147 
1148 #ifdef CONFIG_PM_SLEEP
1149 static int fsmc_nand_suspend(struct device *dev)
1150 {
1151 	struct fsmc_nand_data *host = dev_get_drvdata(dev);
1152 
1153 	if (host)
1154 		clk_disable_unprepare(host->clk);
1155 
1156 	return 0;
1157 }
1158 
1159 static int fsmc_nand_resume(struct device *dev)
1160 {
1161 	struct fsmc_nand_data *host = dev_get_drvdata(dev);
1162 
1163 	if (host) {
1164 		clk_prepare_enable(host->clk);
1165 		if (host->dev_timings)
1166 			fsmc_nand_setup(host, host->dev_timings);
1167 		nand_reset(&host->nand, 0);
1168 	}
1169 
1170 	return 0;
1171 }
1172 #endif
1173 
1174 static SIMPLE_DEV_PM_OPS(fsmc_nand_pm_ops, fsmc_nand_suspend, fsmc_nand_resume);
1175 
1176 static const struct of_device_id fsmc_nand_id_table[] = {
1177 	{ .compatible = "st,spear600-fsmc-nand" },
1178 	{ .compatible = "stericsson,fsmc-nand" },
1179 	{}
1180 };
1181 MODULE_DEVICE_TABLE(of, fsmc_nand_id_table);
1182 
1183 static struct platform_driver fsmc_nand_driver = {
1184 	.remove = fsmc_nand_remove,
1185 	.driver = {
1186 		.name = "fsmc-nand",
1187 		.of_match_table = fsmc_nand_id_table,
1188 		.pm = &fsmc_nand_pm_ops,
1189 	},
1190 };
1191 
1192 module_platform_driver_probe(fsmc_nand_driver, fsmc_nand_probe);
1193 
1194 MODULE_LICENSE("GPL v2");
1195 MODULE_AUTHOR("Vipin Kumar <vipin.kumar@st.com>, Ashish Priyadarshi");
1196 MODULE_DESCRIPTION("NAND driver for SPEAr Platforms");
1197